Short version:
Focus mode for modern SharePoint pages allows you to focus on a greater amount of page content by hiding the site header, site navigation, and global navigation bar with one click. Roll out start in early May and should be complete by late May for most of us.
Details:
Your SharePoint page viewers will now be able to clean your field of vision and focus on page content by clicking the Expand content button on the command bar to hide the site header, site navigation, and global navigation bar.
This larger content viewing pane in Focus mode will continue as you navigate and select other links to open pages within the same site.
The larger content viewing pane will not continue when you select links to pages outside of the site, even if they are within a hub site.
Compare the the two views below:
Availability:
Roll out start in early May and should be complete by late May for most of us.
